[jismail]

Hi folks,

It was suggested in another site's forum that shooting .308 commercial ammunition in a 7.62 weapon can damage the rifle - very similar to the concerns of shooting 5.56 in a .223rem rifle.

I have heard of the .223 dangers as well as Garand 30.06 ammo restrictions, but never of any .308 concerns.

Is this a real concern or was the post in the other forum incorrect in their statment that you should not shoot .308 commercial in a 7.62?

 

[Stg1944]

This should get you started.

http://m14forum.com/ammunition/100445-7-62-x-51-cartridge-vs-308-winchester-differences.html

 

[jismail]

Thanks for the link.

So... concidering that most of the new para-military rifles say "7.62" on them, and seeing in the linked thread that there is only mininimal pressure differnces in the two cartridge specs when both using the same scale, is it safe to assume current M1A's and M14 Chinese copies are designed strong enough to use standard .308?

 

[win308]

"is it safe to assume current M1A's and M14 Chinese copies are designed strong enough to use standard .308?"


YES..it's OK to interchange SAMMI spec .308 for 7.62 NATO ammo.

 

[slimj]

If you buy a new SAI M1A rifle it is chambered for .308 Winchester and always has been. Unless it is a 7mm08 or .243.

So you can shoot either 7.62X51mm NATO or .308 winchester with Bullet weights between 110 grains and 180 grains.

 

[82nd ABN]

You might want to give this a look over
http://m14forum.com/gus-fisher/66601-little-bit-everything-do-headspace.html

 

[Swamp Rat]

What firearm are you shooting it from?

FYI, I shoot .308 ammo out of my 7.62 marked DPMS rifle all the time. I even go further and shoot Hornady Superformance out of it with no problems.

I wouldn't worry about it, unless you are shooting a NATO surplus rifle.

 

[Seventh Fleet]

"is it safe to assume current M1A's and M14 Chinese copies are designed strong enough to use standard .308?"


YES..it's OK to interchange SAMMI spec .308 for 7.62 NATO ammo.

It depends on if your Chinese rifle has had the bolt changed to USGI and the head space set to .308 Winchester SAAMI specs which is what M-1A's are set for from the factory.

The Polytechs however are set to 7.62x51 NATO specs which is far more generous, since they are set up like USGI M-14's when it comes to head spacing. This is because 7.62 NATO has a much more generous chamber than .308 since it is a military rifle and is subject to be used in harsh conditions where reliability is paramount.

I would not shoot .308 Winchester in any M14 or Chinese M14 if the head space has not been set to .308 SAAMI specs so for safety sake make sure of your head space before
firing it for the first time.

This link will clarify it for you... http://www.303british.com/id36.html

7th

 

[TexIndian]

I've always used either kind of ammo in my guns without any problems. I've done the same with .223 as well. But then again, all my non-military guns are big strong guns and my semi-autos are too. I don't have a Chinese gun (not meant to criticize those that do, I just don't happen to have one).

 

[kodiakkid]

It depends on if your Chinese rifle has had the bolt changed to USGI and the head space set to .308 Winchester SAAMI specs which is what M-1A's are set for from the factory.

The Polytechs however are set to 7.62x51 NATO specs which is far more generous, since they are set up like USGI M-14's when it comes to head spacing. This is because 7.62 NATO has a much more generous chamber than .308 since it is a military rifle and is subject to be used in harsh conditions where reliability is paramount.

I would not shoot .308 Winchester in any M14 or Chinese M14 if the head space has not been set to .308 SAAMI specs so for safety sake make sure of your head space before
firing it for the first time.

This link will clarify it for you... http://www.303british.com/id36.html

7th

What does the head space have to be to be .308 SAAMI specs

 

[Larry Gibson]

You might want to give this a look over
http://m14forum.com/gus-fisher/66601-little-bit-everything-do-headspace.html

I've a lot of respect for Gus but I've a problem with this statement; "1. Do NOT use standard Nato Spec surplus ammo in a rifle chambered with a NM chamber and set up at the minimum headspace. Even if the rifle functions with no apparent problems, the chamber pressure of each round fired is significantly more than in a proper Nato Spec chamber." The reason is he makes an assumption based on measuring headspace. I wouldn't want to guess at the number of match shooters over the years shooting M1A/M14s with NM who have shot the barrels out using "Nato spec" ammuntion, i.e. M80 XM118, M118, M118 and now M118LR. All without any said pressure problems alluded to.

Additionally I have measured the pressure of those ammuntions in a minimum spec chamber with minimum headspace and another test barrel with a NM chamber with minimum headspace. The measured pressures showed nothing out of the ordinary for such loads and were perfectly within NATO specs and below SAAMI MAP for the .308W. I've also pressure tested numerous foreign lots of 7.62 ammuntion of Nato spec and not of Nato spec. Additionally I've pressure tested numerous brands of .308W commercial ammuntion. The psi MAPs of .308W commercial ammuntion overlaps with those of US made 7.62 Nato with some of each having higher MAPs than the other. Thus it is foolish to say one or the other is loaded to "higher pressure". I wonder if Gus realises that 7.62 Nato Spec ammuntion is developed with safe pressures in test barrels with minimum chambers, smaller than NM chambers? Thus firing those cartridges in slightly larger NM chambers should give less pressure.

.308W or 7.62 NATO.....Much ado about nothing........

And yes I have fired lots of commercial .308W ammuntion through M1A/M14s over 41+ years, some with NM chambers with minimum headspace and others were rack grade rifles with milspec chambers. Not a single problem.

Larry Gibson

 

[82nd ABN]

Hi Larry your clearly entitled to your own opinion based on data you have collected over the years. This has been a gray area for me as well as others since I joined the forum. It comes up over and over again. I have not done anything like you in your efforts to support what you said. It was actually this thread that inspired me to ask my own headspace question. Here is the link
http://m14forum.com/gunsmithing/104319-my-turn-ask-head-space-question-please.html
Although I am glad you have never had any problems and your data is well founded, I am going to stick with what a man with way more experience than most fiddling around with these rifles has to say. In my mind I feel they are correct, it just makes sense. Not to mention all the malfunctions that the man has seen caused by the same thing we agree to disagree on. Not looking to discredit you or call you out so to speak. Please don't take what I said as someone looking for an argument please. Had enough of that over the years.

 

[NE450N02]

As I stated in another thread, so I will be brief here.

I have fired thousands, and thousands of 308 ammo and 7.62x51 ammo, marked NATO from the US and other clountries, and 7.62x51 ammo not marked NATO, in rifles marked 308 or 7.62x51 with NO problems.

This includes factory rifles, custom hunting, Sniper, and match rifles, single shot, bolt, lever, and semiauto.

I have never had a single problem.

Now I will state that before I bought any surplus 7.62x51 ammo I did some research to make sure the surplus ammo was not known to have any quality problems.

In fact most of the different overseas surplus 7.62x51 ammo has been more accurate than US M80 NATO ball.

 

[M1A's r BEST]

So, when I reload for my M1A (as I've done since 1978) am I using .308 Winchester reloading data or 7.62X51 reloading data?

That's a question I think I know the answer to but I'd like other folks to think about it. I have about 6 or 7 reloading manuals and none of them have a 7.62X51 section in them. I've heard one of the newer Hornady manuals does but the point is that any of us who reload have been using books/data that say ".308 Winchester" on the page.

I've not shot a lot of commercial ammo through my M1A. Maybe 3 or 4 boxes over the years if I found a box or two somewhere for a price I couldn't pass up. Then I shot it up and reloaded the brass.

My rifle came new with a commercial NM barrel on it and I've never had an issue with surplus, commercial or reloads. I don't remember what the headspace was but I know I checked it back when I was fitting an H&R bolt to my son's PolyTech rifle just for comparison sake and the PolyTech ended up being slightly "tighter" than my SA.

I guess if my rifle was going to have problems it would have been many years ago. After 30 years something might wear out but anything that would have broken would have broken by now.

I too shoot surplus or commercial ammo in my AR15's and my M700 Remington. My brother was shooting surplus 5.56X45 ammo in his Savage .223 Rem. varmint rifle.

My experience, and the experience of others, is just that - my memory of things I did and observed with my rifle, my ammo, etc. Your rifle is most likely different so you'll have to take what I say with a grain of salt, and observe your own ammo and rifle as you shoot it so you can decide for yourself what works for you.

Good luck.

 

[82nd ABN]

Thanks much appreciate the input. I don't want you to think I'm telling any of you your wrong. Like you said what works for you. I think it is safe to shoot NATO ammo through an chamber that has ample room just not one that is tight like the way I set mine up to 1.630-1.631. I don't know what the magic number is to be considered ok. Each and everytime I ordered an AR barrel from Krieger they ask me how I want it chambered, for 5.56 or .223. They ask what I'll be shooting. I have a bunch of 75 gr BTHP commercial ammo. I typically get a Wyler chamber which will safely allow me to shoot both. I believe there has to be something to it if they are asking or do you think there just covering there hind quarters?

 

[nf1e]

I have been using .308 and 7.62 interchangably for over 45 years in most of my rifles. I don't use any pills over 180 gr. No problems yet. Not to say that Murphy won't pop up his ugly head. Just went over chambers and they vary from 1.631 to 1.634. My receivers are Polytech, SAI, and LRB. I have been using 5 to 8k rounds per year and change barrels when I get the itch. I may be ugly, but its not from eating rifle parts.
Semper Fi
Art

 

[82nd ABN]

5-8K per year! God bless ya Art. I guess I will continue to sit on the fence over this one. You all seem to be pretty good authorities with vast amounts of experience, far more than I will ever dream to have. I don't want to sound like I am disputing anyones authority/combined experience here. All I can do is digest everything I read and come go my own conclusions. This controversy, if you want to call it that, has inspired me to make a few calls to a few barrel makers over the next couple of days. I am curious to see what they have to say, I wonder if their opinions will be as varied as those on the forum. If anyone cares to know what they say, I would be glad to post the comments in this thread. I just don't want to come across as a know it all because it's gents like those that posted here as well as Art, Gus and Ted that I am continually learning from. I appreciate you all tolerating my doubt and entertaining my thoughts without becoming angry with me.

 

[BigBill]

Food for ammo facts;

With all surplus military rifles and some new modern versions some are ammo finiky and manufactured for the 7,62/308 nato round only. Some can't handle the full pressure 308 winchester round. At the sametime they can't handle and aren't built to shoot heavier bullets than the 168gr in the 308 winchester ammo. In my spanish Cetme and my french 49/56 converted to 308 i only shoot the surplus military 308 nato south african ball ammo. Keeping in mind some rifles have fluted chambers so the thicker wall nato case is stronger and won't blow out.

I think we should beaware that what gun can handle what ammo when we get away from the m14/m1a's in 308 with the other semi auto military guns. I research before i shoot.

 

[nf1e]

Warren, 5-8k per year is not that much. My range is all off 100 feet from my office. When I get tired of dealing with customers, which is more and more often as the years go by, I walk out and run a couple of mags at silouets. Sometimes on the weekend when we have company, it is nothing to go through 3or 4 hundred rounds. Got to make sure all the rifles work , just in case.
Semper Fi
Art

 

[slimj]

I think where the Misunderstanding with this whole thing lies is that M14s (Real Government M14s which 99.9% of us on this board do not have) were chambered in 7.62X51mm NATO Not .308 Winchester.....

However Every Commercial M1A or M14 Semi Auto Rifle I know of (Which 99.9% of us on this board do have) is Chambered for .308 Winchester. It is safe to shoot the 7.62X51mm NATO and .308 Wincheser in a .308 Winchester Chamber. So for the Vast Majority of us this is a non issue.